5KP8.5-B Equivalent & Substitute Parts

Part Overview

The 5KP8.5-B is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose transient voltage protection applications. This component features an 8.5V reverse standoff voltage rating and 5000W peak pulse power handling capability in a P600 axial through-hole package. The part is currently listed as obsolete, necessitating identification of active equivalent alternatives that maintain electrical and mechanical compatibility for ongoing system support and new designs.

Substiute Parts

5KP8.5-B

Littelfuse Inc.In Stock: 9875KP8.5-B Datasheet

Current PartRFQ

5KP8.5A

LittelfuseIn Stock: 3001105KP8.5A Datasheet

DirectRFQ

5KP8.5A-B

Littelfuse Inc.In Stock: 11895KP8.5A-B Datasheet

DirectRFQ

SA8.5A

Taiwan Semiconductor CorporationIn Stock: 8461SA8.5A Datasheet

MFR RecommendedRFQ

5KP8.5E3/TR13

Microchip TechnologyIn Stock: 12205KP8.5E3/TR13 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 5KP8.5-B is determined by the following critical parameters:

• Voltage - Reverse Standoff (Typ): Must be 8.5V to maintain circuit protection threshold
• Unidirectional Channels: Must be 1 (single channel configuration)
• Type: Must be Zener diode
• Mounting Type: Must be Through Hole for PCB compatibility
• Package / Case: P600 or DO-204AC (DO-15) axial packages are mechanically compatible
• Operating Temperature Range: Must support -55°C ~ 175°C (TJ)
• RoHS Status: Must maintain ROHS3 compliance

Substitute parts are grouped into two categories based on package compatibility:

Category A - P600 Package (Direct Package Match):

• 5KP8.5A (Littelfuse, Active)
• 5KP8.5A-B (Littelfuse, Active)
• 5KP8.5E3/TR13 (Microchip Technology, Active)

Category B - DO-204AC (DO-15) Package (Alternative Package):

• SA8.5A (Taiwan Semiconductor Corporation, Active)

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (P600 Package Category):

The 5KP8.5A and 5KP8.5A-B are direct functional equivalents manufactured by Littelfuse Inc. Both parts maintain the same reverse standoff voltage (8.5V), package form factor (P600), and 5000W peak pulse power rating. These parts are in active production status with established supply chains. The 5KP8.5A is supplied in Tape & Reel packaging, while the 5KP8.5A-B is supplied in Bulk packaging. Selection between these two depends on procurement and assembly requirements.

The 5KP8.5E3/TR13 manufactured by Microchip Technology is an active alternative with identical voltage and power specifications. This part is supplied in Tape & Reel format and maintains P600 package compatibility. The clamping voltage (15.9V) is slightly higher than the original part, remaining within acceptable tolerance for general-purpose transient suppression applications.

Secondary Substitute (DO-204AC Package Category):

The SA8.5A manufactured by Taiwan Semiconductor Corporation is an active alternative with matching voltage specifications and operating temperature range. This part uses the DO-204AC (DO-15) axial package, which differs mechanically from the P600 package. The SA8.5A has reduced peak pulse power handling (500W versus 5000W) and lower peak pulse current (36A versus 354.2A). This part is suitable only for applications where the lower power rating is acceptable.

All substitute parts maintain ROHS3 compliance and unlimited moisture sensitivity level (MSL 1), ensuring compatibility with modern manufacturing and environmental standards.

Frequently Asked Questions (FAQ)

Q: Can the 5KP8.5A directly replace the 5KP8.5-B without PCB modifications?

A: Yes. The 5KP8.5A maintains identical P600 axial package dimensions and through-hole lead spacing, enabling direct substitution without PCB layout changes. Both parts are unidirectional Zener TVS diodes with 8.5V reverse standoff voltage and 5000W peak pulse power rating.

Q: What is the difference between 5KP8.5A and 5KP8.5A-B?

A: Both parts are electrically identical with matching voltage and power specifications. The difference is packaging format: 5KP8.5A is supplied in Tape & Reel (TR) format for automated assembly, while 5KP8.5A-B is supplied in Bulk format for manual handling or alternative assembly processes.

Q: Is the 5KP8.5E3/TR13 a suitable replacement?

A: Yes. The 5KP8.5E3/TR13 maintains the same reverse standoff voltage (8.5V), P600 package, and 5000W peak pulse power rating. The clamping voltage is 15.9V compared to the original 15.12V, representing a 5% increase that remains within acceptable tolerance for general-purpose transient suppression.

Q: Can the SA8.5A replace the 5KP8.5-B?

A: The SA8.5A is electrically compatible for voltage protection (8.5V standoff, 14.4V clamping) but has reduced power handling capability (500W versus 5000W). This part is suitable only for low-energy transient suppression applications. The DO-204AC (DO-15) package differs from P600, requiring PCB layout verification for lead spacing compatibility.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. All substitute parts listed (5KP8.5A, 5KP8.5A-B, 5KP8.5E3/TR13, and SA8.5A) maintain ROHS3 compliance and are suitable for applications requiring environmental and regulatory compliance.

Q: What is the operating temperature range for these TVS diodes?

A: All parts, including the original 5KP8.5-B and all substitutes, operate across the temperature range of -55°C to 175°C (junction temperature), ensuring compatibility across industrial and commercial applications.